1. Field of the Invention
The present invention relates to a motor stop control device for a reel-type gaming machine, the motor stop control device having a motor with two pairs of excitation phases and stopping the motor according to an instruction command transmitted from an external.
2. Description of Related Art
Conventionally, in a symbol variable rotation device utilized in a reel-type gaming machine (for example, a Japanese Pachi-slot machine), a reel is directly connected to a rotor of a stepping motor (abbreviated as “direct drive manner”) as shown in Japanese Unexamined Publication No. 10-71240.
However, in the above direct drive manner, since it is not provided a mechanical speed reduction device the stepping motor has to produce rotation torque corresponding to inertia of the reel. Therefore, it is adopted an expensive stepping motor (for example, hybrid-type stepping motor), which can produce high torque. Thus, there is a problem that production cost of the reel unit including the stepping motor cannot be remarkably reduced.
Further, in reel control in the above direct drive manner, the stepping motor is controlled and stopped according to all-phase excitation, and it is generally used a manner in which detent torque in the stepping motor is utilized. However, there is imbalance in the detent torque every reel and is also imbalance in the above inertia every reel. Therefore, stop of symbol on the reel becomes unstable, as a result, the symbol described on the surface of the reel cannot be precisely stopped.
Further, in order to avoid imbalance in the symbol stop position, an assembler must conduct select work to make imbalance of the detent torque in the stepping motor narrow and adjust a balance (balance adjustment) between the detent torque and the inertia of the reel (moment of inertia) by spots. In this case, there is a problem that manday increases when the assembler assembles the reel unit.